Back in bygone days I did take a nice piece of Master chalk now and then. I also spent over a hundred a week in pool halls so it didn't keep me up nights! The issue wasn't an unwillingness to buy chalk but not a clue where to buy it. When I found chalk for sale in stores it would be crap, not Master blue which was the only chalk I wanted to use. Master green was dryer and dustier.
With the internet I bought a gross of Master blue. I deliberately leave almost new chalk everywhere I play. Best I recall I paid sixteen or seventeen cents a piece for that chalk. Funny thing, I did an accidental social experiment. I dried a few dozen pieces of chalk in the oven to see if it would play better. I wrapped these pieces of chalk in green electrical tape to tell which were mine and to keep them dry. When they got a little wear I left them on the table as usual. It was amazing how many people would walk the length of the pool room to bring me my chalk they thought I forgot. This was in Buffalo's pool room on Airline, a place in a rough part of town with plenty of questionable clientele.
About the experiment, my dried chalk played better. Then I accidentally left a piece on my back patio for months. Coulda almost wrung this chalk out in South Louisiana near New Orleans. It played better too! Amazingly, Tweetem had selected the worst possible moisture content for their chalk! Well, possibly it was all in my head. Experiments with chalk are over. I collected a cube or three of different premium chalk and toted them in my case for a few years. Gave them to a friend that would use them. I carefully chalk with Master chalk at the beginning of a game and before I am going to use extreme spin. Miscues are almost as rare as hen's teeth. I would have paid for the high dollar chalk in my gambling days if I thought it would help my game, we paid four hundred and twenty dollars a night for a set of goodyear gumballs for the race car. When mine was slow, I could often make it go much faster for a few hundreds of dollars. When it was a top car it might take a half dozen or more changes and a thousand dollars or more to gain a tenth of a second. Twenty or forty dollars for a cube of chalk that would make me hundreds would have seemed reasonable. Seventeen cents for a cube of chalk that is going to make me the same money seems even more reasonable. Master blue rocks and I still have enough left from that gross to last out my life.
PT109, what is the physics behind the gravitational pull of chalk for other pieces of chalk? I used to strategically place two or three pieces of newish Master chalk around the table where it would always be close to hand. Within three to six games it would all be in a pile. Spread the chalk, it would soon congregate again. I consider chalk's attraction to chalk one of the mysteries of the universe!
Hu
I call them.....uh curtosy chalk. Kinda like spreading the love. And a just in case back up with Karma. 
Since I am in charge of purchasing. The wife is in charge of distribution. 
It's Social Intercourse. Shrug
Lol.
